1. Field of the Invention
The present invention relates to a novel sea-land-sky craft capable of climbing vertically, flying horizontally, hovering in the air, running on the ground and navigating on the water while interchanging these individual functions simply and reliably.
2. Background of the Invention
As the flying system having the three functions of climbing vertically, flying horizontally and hovering in the air, the rotorcraft (here called the xe2x80x9chelicopterxe2x80x9d), the vertical take-off and landing (as will be called the xe2x80x9cVTOLxe2x80x9d) fixed-wing craft and so on are known not only to those skilled in the art but also widely in the world. However, these crafts have the following many problems.
The helicopter of the prior art has high efficiencies for climbing vertically and hovering in the air but has a problem that the efficiency for flying horizontally is extremely poor. On the contrary, the VTOL of the prior art has high efficiencies for flying horizontally but has a problem that the efficiencies for climbing vertically and hovering in the air are extremely poor. In addition, both of these have serious defects that they are so unstable maintaining position in the air that they easily turn over and are more difficult to maneuver than the ordinary fixed-wing craft and are highly prone to turning over or dropping. Moreover, the helicopter and the VTOL of the prior art cannot run on a road or waterway of a small width and require a road as wide as a runway or a waterway as wide as a large river.
An object of the present invention is to provide an improved small-sized inexpensive sea-land-sky craft which not only can solve all the individual problems, difficulties, defects and restrictions of the aforementioned helicopter and VTOL of the prior art but also is highly efficient in all the functions to climb vertically, fly horizontally, hover in the air, run on the road and navigate on the waterway and able to interchange those individual functions safely, reliably and easily.
In order to achieve the above-specified object, the sea-land-sky craft of the invention improves the flying efficiency while climbing vertically and hovering in the air by disposing a cylindrical duct by the outer periphery of the rotors. At the horizontally flying time, the propelling efficiency is enhanced by inclining the fuselage forward by 90 degrees and by changing the diameters and the angles of incidence of the rotors. At the same time, the shape of the duct enclosing the rotors is changed from a cylindrical shape into an elliptical cylinder wing or a straight line wing to deform the craft into an airplane having a similar shape as an ordinary one having fixed main wings, thereby to improve the flying efficiency for a horizontal flight drastically. At the same time, the shape of the cylindrical duct having a large diameter is changed into an elliptical cylinder rotor of a shorter diameter or a straight line wing of a small width, and the craft may run or navigate in the longer diameter direction of the elliptical cylinder rotor or in the longitudinal direction of the straight line wing even on a narrow road or waterway so that it may reach a destination easily.
An aspect of the present invention resides in a sea-land-sky craft which comprises rotating wings rotatable in opposite directions on their centers. Mounting shafts are disposed at positions eccentric to the centers of the rotating wings and mount the rotating wings so that the orientation of the rotating wings can be turned. A cylindrical duct encloses the outer circumferences of the maximum diameters of the rotations of the rotating wings. A fuselage is located at a central portion of the craft. Movable struts are provided for connecting the cylindrical duct and the fuselage. In the sea-land-sky craft, the cylindrical duct is deformed into a fixed wing by the actions of the movable struts.